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1.
荔枝壳红色素的提取及稳定性观察   总被引:4,自引:0,他引:4  
以荔枝壳为原料,在酸性条件下浸提荔枝壳红色素,并对其稳定性进行了研究,结果表明,该色素在酸性条件下对光、热、常用食品添加剂均具有较好的稳定性。  相似文献   
2.
中药材龟板和鳖甲中DNA的提取与扩增   总被引:22,自引:0,他引:22  
中药材龟板和鳖甲中DNA的提取与扩增王亚明,周开亚,吴平,徐珞珊(南京师范大学生物系,南京210097;中国药科大学生药学研究室,南京210009)龟鳖类药材在我国使用历史悠久,具补阴益气的功效。《中国药典》(1990年版)规定龟甲(龟板)的原动物为...  相似文献   
3.
Conventional tube cell culture has been recognised as the most sensitive technique available for human cytomegalovirus (HCMV) detection. Low-speed centrifugation of specimen inocula onto cell culture monolayers has been shown to increase the efficiency of infection with the AD 169 strain of HCMV. Therefore a centrifugal force of 900g for 1 hour at 37 degrees C was used to enhance the detection of HCMV cytopathic effect (CPE) in shell vials that contained circular coverslips with a monolayer of human embryonic lung (HEL) fibroblasts. Of 195 specimens, HCMV CPE was detected in 18 specimens (9.02%) on shell vial culture assay, whereas conventional tube cell culture was positive in only 13 specimens (6.6%). The shell vial culture assay was significantly more sensitive (P less than 0.05). Furthermore the development of the cytopathic effect on shell vial culture assay was significantly earlier (P less than 0.01) and more extensive. Urine samples were sonicated and the results obtained with immunofluorescence using human immune serum demonstrated that sonication increased both the intensity of fluorescence and number of fluorescent foci of HCMV-infected cells and also decreased the non-specific fluorescence of the background.  相似文献   
4.
应用PHA-L和Biocytin两种神经示踪物对非鸣禽环鸽(Streptopeliarisoria)中脑半圆隆枕(torussemicircularis)的传出投射进行了分区研究。结果发现半圆隆枕丘间核内缘(ICM)发出两束纤维分别向尾端投射至外侧丘系背核腹侧(LLDv)周围和向首端投射至丘脑卵形壳(Ov-shell);丘间核(ICo)发出的纤维直接投射至下丘脑前内侧核(AM)。从脑桥至听丘各级听神经核周围,均存在疏松网状神经纤维结构区,它们相互连接形成了一条与经典听觉神经通路相平行的旁听觉神经通路。这是首次关于鸟类发声、听觉和内分泌三维系统存在直接神经环路联系的较为完正的报道。  相似文献   
5.
Seventy-five organ transplant recipients underwent prolonged virological and serological follow-up for early detection of human Cytomegalovirus (HCMV) infection after transplantation. HCMV DNA detection by nested polymerase chain reaction (PCR) and HCMV early structural antigen (pp65) detection were carried out in 576 peripheral blood leucocyte (PBL) samples. Furthermore, 563 blood specimens were investigated by a commercially available enzyme-linked immunosorbent assay (ELISA) for the detection of specific immunoglobulins G, M, and A against HCMV structural antigens. In eight of nine symptomatic organ transplant recipients, HCMV DNA was detected in one or more consecutive blood samples. HCMV DNA PCR was also positive in one or more samples from eight patients who never developed HCMV-related symptoms. HCMV pp65 antigen was detected almost exclusively in PBL samples from organ transplant recipients suffering from HCMV disease. However, antigenaemia was not detected in four PCR positive patients presenting clinical signs attributable to HCMV infection. Two of the initially HCMV DNA positive samples were not confirmed by retesting and hybridisation. The results of the present study demonstrate that despite the high specificity of nested PCR, HCMV DNA may be detected in the absence of clinical symptoms attributable to HCMV infection. In asymptomatic reactivation, limited replication of viral DNA may be responsible for positive results of PCR without any clinical relevance. In this context, pp65-antigen detection from PBL seems to have a better prognostic value, but is not always detected when clinical symptoms are present. © 1994 Wiley-Liss, Inc.  相似文献   
6.
Eleven hundred and thirty-three clinical specimens submitted to the laboratory for diagnosis of respiratory virus infections were tested by direct immunofluorescence (DIF) for respiratory syncytial virus (RSV), by shell vial culture, and by conventional cell culture. The shell vial cultures were stained with 8 different monoclonal antibodies both 1 day and 3-7 days after inoculation. In order to limit the cost and the workload, mixtures of monoclonal antibodies were used. Coverslips with HEp-2 cells were incubated with a mixture of FITC-labeled monoclonal antibody to RSV and nonlabeled monoclonal antibody to adenovirus. When no RSV positive IF staining was observed after the first incubation step, the same coverslip was incubated once more with FITC-labeled anti-mouse antibody. A positive reaction at this stage indicated the presence of adenovirus. Similarly, cultures of tertiary monkey kidney cells were investigated with a mixture of two FITC-labeled monoclonals to the influenza viruses A and B and three nonlabeled monoclonals to the parainfluenza viruses 1, 2 and 3. If influenza virus or parainfluenza virus was detected, the exact type was determined by staining different parts of a duplicate coverslip. Shell vial cultures for cytomegalovirus (CMV) were always performed separately on human embryonic lung fibroblasts. Using this approach, we detected RSV (n = 248), CMV (n = 42), parainfluenza virus (n = 31), influenza virus (n = 28), and adenovirus (n = 6), in most cases after only one day of culture. For RSV, the sensitivity of the shell vial method was too low (74%) to allow omission of DIF (sensitivity 95%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
8.
国外口服软胶囊剂的研究   总被引:9,自引:0,他引:9  
崔颖  屠锡德 《药学进展》2003,27(6):340-345
从内容物和胶壳两个方面综述国外口服软胶囊剂的研究进展。口服软胶囊剂与其他传统剂型如片剂、硬胶囊剂、颗粒剂以及溶液剂等相比,具有生物利用度高、药物稳定性良好、含量准确等优点。  相似文献   
9.
含罂粟壳中成药质量标准分析   总被引:1,自引:0,他引:1  
罂粟壳属于麻醉药品管理。目前已上市的部分中成药处方中含有罂粟壳,针对罂粟壳使用的特殊要求,我们对含罂粟壳中成药质量标准进行了分析,对存在的问题进行了探讨。  相似文献   
10.
《Acta biomaterialia》2014,10(5):2112-2124
The present study reports an engineered poly-l-lactide-co-glycolic acid (PLGA)–casein polymer–protein hybrid nanocarrier 190 ± 12 nm in size entrapping a combination of chemically distinct (hydrophobic/hydrophilic) model drugs. A simple emulsion–precipitation route was adopted to prepare nearly monodispersed nanoparticles with distinct core/shell morphology entrapping paclitaxel (Ptx) in the core and epigallocatechin gallate (EGCG) in the shell, with the intention of providing a sequential and sustained release of these drugs. The idea was that an early release of EGCG would substantially increase the sensitivity of Ptx to cancer, thereby providing improved therapeutics at lower concentrations, with less toxicity. The hemo- and immunocompatibility of the core/shell nanomedicine was established in this study. The core/shell nanoparticles injected via the tail vein in Sprague–Dawley rats did not reveal any organ toxicity as was evident from histopathological evaluations of the major organs. In vivo pharmacokinetic studies in rats by high-performance liquid chromatography confirmed a sustained and sequential release of both the drugs in plasma, indicating prolonged circulation of the nanomedicine and enhanced availability of the drugs when compared to the bare drugs. Overall, the polymer–protein multilayered nanoparticles proved to be a promising platform for nanopolypharmaceutics.  相似文献   
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